My heating/AC unit just died very suddenly. I bought this house in Florida just over ten years ago brand new. I've had this HVAC system checked out and serviced every year since. It was last inspected recently--12/10/2012--and all seemed fine. Yesterday I tried to send up some heat and it was dead as a doornail... not a sound, no fan, etc. I checked the circuit breaker... even turned it off and back on to be sure... but nothing. I tried the AC... nothing either. What could have broken so suddenly and completely? Could it possibly be the thermostat? It's very out of date by today's standards... very difficult to move the little "toggles" back and forth. I'll probably have to call the company I deal with eventually, but I know the service call alone is probably close to $100 and I'd love to have some idea of what the problem could be? I'm on a fixed income, so I'd appreciate any ways to save a little money.

Thank you in advance.

Have you used the heat or A/C since it was serviced?

Have you used the heat or A/C since it was serviced?

Yes, I used the heat once or twice in the evening. It seemed fine, but honestly I wasn't paying too much attention if there were any unusual sounds or anything. It did send up the heat.

If this is a package unit with no indoor part, turn off the breaker(s) to the unit & remove the acess panel. Inside should be a place where the thermostat wires connect. They may be inside another box which will have to be opened. Look for an automotive type fuse (usually either 3 or 5 amp). Remove it & check to see if it is blown. If so, install a new one, turn on the power & try it. If it blows again, you will need to call for service.